The present invention relates to a key switch which can be conveniently assembled and which has a low profil while can have a sufficient vertical travel when it is depressed to input a signal to a computer.
The most common way of inputting information into a computer is through a keyboard including a number of key switches to be depressed. Each key switch must have a sufficient vertical displacement to activate the switch whereby the key switch will not be too sensitive to control. As computers become smaller and lighter, key switches of a keyboard should be designed to have a limited height.
Referring to FIG. 1, a key cap 92 of a key switch 90 is mounted on a support board 94. A plunger 96 of the key cap 92 compresses a rubber spring 98 causing vertical displacement thereof. The plunger 96 must have a sufficient vertical displacement to be inserted into the support board 94, otherwise the key cap 92 may become locked. However, since the plunger 96 is integral, it has a quite large height to implement the sufficient vertical displacement.
Referring to FIG. 2, a key switch 80 comprises a linkage group 82 comprising links connected together by engaging means. The ends of the linkage group 82 are mounted to a key cap 84 and a support board 86, respectively. Since the linkage group must be accurately assembled, assembly becomes time consuming. Hence, a key switch which can be easily assembled and which promotes conservation of space is requisite.
The related prior art is disclosed in U.S. Pat. Nos. 5,457,297; 5,463,195; 5,512,719.